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Section 6 ROM
Rev. 6.00 Sep 12, 2006 page 147 of 526
REJ09B0326-0600
Examples:
Sample calculations when executing a program in on-chip memory (RAM) at an operating
frequency of 6 MHz
a (
φ
) =
×
9 = 10.8
≈
10 = H'000A
b (
φ
) =
×
4 = 4.8
≈
5 = H'05
c (
φ
) =
×
2 = 2.4
≈
3 = H'03
d (
φ
) =
×
1953 = 2343.6
≈
2343 = H'0927
6
5
6
5
6
5
6
5
Table 6.12 Watchdog Timer Overflow Interval Settings (Set Value of #e for Operating
Frequencies)
Oscillation
Frequency
f
OSC
= 16 MHz
f
OSC
= 10 MHz
f
OSC
= 8 MHz
f
OSC
= 2 MHz
Operating
Frequency
Variable
φφφφ
= 8 MHz
φφφφ
= 5 MHz
φφφφ
= 4 MHz
φφφφ
= 1 MHz
e (
φ
)
H'9B H'DF H'E5 H'F7
6.7.7 Prewrite-Verify
Mode
Prewrite-verify mode is a verify mode used to all bits to equalize their threshold voltages before
erasure.
To program all bits, write H'00 in accordance with the prewrite algorithm shown in figure 6.15.
Use this procedure to set all data in the flash memory to H'00 after programming. After the
necessary programming time has elapsed, exit program mode (by clearing the P bit to 0) and select
prewrite-verify mode (leave the P, E, PV, and EV bits all cleared to 0). In prewrite-verify mode, a
prewrite-verify voltage is applied to the memory cells at the read address. If the flash memory is
read in this state, the data at the read address will be read. After selecting prewrite-verify mode,
wait at least 4 µs before reading.
Note: For a sample prewriting program, see the prewrite subroutine in the sample erasing
program.
Summary of Contents for F-ZTAT H8/3642A Series
Page 6: ...Rev 6 00 Sep 12 2006 page iv of xx ...
Page 8: ...Rev 6 00 Sep 12 2006 page vi of xx ...
Page 22: ...Rev 6 00 Sep 12 2006 page xx of xx ...
Page 124: ...Section 5 Power Down Modes Rev 6 00 Sep 12 2006 page 102 of 526 REJ09B0326 0600 ...
Page 188: ...Section 6 ROM Rev 6 00 Sep 12 2006 page 166 of 526 REJ09B0326 0600 ...
Page 190: ...Section 7 RAM Rev 6 00 Sep 12 2006 page 168 of 526 REJ09B0326 0600 ...
Page 298: ...Section 9 Timers Rev 6 00 Sep 12 2006 page 276 of 526 REJ09B0326 0600 ...
Page 378: ...Section 12 A D Converter Rev 6 00 Sep 12 2006 page 356 of 526 REJ09B0326 0600 ...
Page 446: ...Section 13 Electrical Characteristics Rev 6 00 Sep 12 2006 page 424 of 526 REJ09B0326 0600 ...